download the turkey energy revolution scenario

GLOBAL ENERGY [R]EVOLUTION
A SUSTAINABLE TURKEY ENERGY OUTLOOK
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the energy [r]evolution | THE “VIRTUAL POWER STATION”
method of storing large amounts of electric power. In a pumped
storage system, energy from power generation is stored in a lake
and then allowed to flow back when required, driving turbines and
generating electricity. 280 such pumped storage plants exist
worldwide. They already provide an important contribution to
security of supply, but their operation could be better adjusted to
the requirements of a future renewable energy system.
In the long term, other storage solutions are beginning to emerge.
One promising solution besides the use of hydrogen is the use of
compressed air. In these systems, electricity is used to compress air
into deep salt domes 600 metres underground and at pressures of
up to 70 bar. At peak times, when electricity demand is high, the air
is allowed to flow back out of the cavern and drive a turbine.
Although this system, known as CAES (Compressed Air Energy
Storage) currently still requires fossil fuel auxiliary power, a socalled
“adiabatic” plant is being developed which does not. To
achieve this, the heat from the compressed air is intermediately
stored in a giant heat store. Such a power station can achieve a
storage efficiency of 70%.
The forecasting of renewable electricity generation is also
continually improving. Regulating supply is particularly expensive
when it has to be found at short notice. However, prediction
techniques for wind power generation have become considerably
more accurate in recent years and are still being improved. The
demand for balancing supply will therefore decrease in the future.
the “virtual power station” 10
The rapid development of information technologies is helping to
pave the way for a decentralised energy supply based on
cogeneration plants, renewable energy systems and conventional
power stations. Manufacturers of small cogeneration plants already
offer internet interfaces which enable remote control of the system.
It is now possible for individual householders to control their
electricity and heat usage so that expensive electricity drawn from
the grid can be minimised – and the electricity demand profile is
smoothed. This is part of the trend towards the ‘smart house’ where
its mini cogeneration plant becomes an energy management centre.
We can go one step further than this with a ‘virtual power station’.
Virtual does not mean that the power station does not produce real
electricity. It refers to the fact that there is no large, spatially
located power station with turbines and generators. The hub of the
virtual power station is a control unit which processes data from
many decentralised power stations, compares them with predictions
of power demand, generation and weather conditions, retrieves the
available power market prices and then intelligently optimises the
overall power station activity. Some public utilities already use such
systems, integrating cogeneration plants, wind farms, photovoltaic
systems and other power plants. The virtual power station can also
link consumers into the management process.
future power grids
The power grid network must also change in order to realise
decentralised structures with a high share of renewable energy.
Today’s grids are designed to transport power from a few centralised
power stations out to the passive consumers. A future system must
enable an active integration of consumers and decentralised power
generators and thus realise real time two-way power and information
flows. Large power stations will feed electricity into the high voltage
grid but small decentralised systems such as solar, cogeneration and
wind plants will deliver their power into the low or medium voltage
grid. In order to transport electricity from renewable generation such
as offshore wind farms in remote areas (see box), a limited number
of new high voltage transmission lines will need to be constructed.
These power lines will also be available for cross-border power trade.
Within the Energy [R]evolution scenario, the share of variable
renewable energy sources is expected to reach about 10% of total
electricity generation by 2020 and about 35% by 2050.
A Greenpeace report shows how a regionally integrated approach to
the large-scale development of offshore wind in the North Sea could
deliver reliable clean energy for millions of homes. The ‘North Sea
Electricity Grid [R]evolution’ report (September 2008) calls for the
creation of an offshore network to enable the smooth flow of
electricity generated from renewable energy sources into the power
systems of seven different countries - the United Kingdom, France,
Germany, Belgium, The Netherlands, Denmark and Norway – at the
same time enabling significant emissions savings. The cost of
developing the grid is expected to be between € 15 and € 20 billion.
This investment would not only allow the broad integration of
renewable energy but also unlock unprecedented power trading
opportunities and cost efficiency. In a recent example, a new 600
kilometre-long power line between Norway and the Netherlands cost
€ 600 million to build, but is already generating a daily cross-border
trade valued at € 800,000. The grid would enable the efficient
integration of renewable energy into the power system across the
whole North Sea region. By aggregating power generation from wind
farms spread across the whole area, periods of very low or very high
power flows would be reduced to a negligible amount. A dip in wind
power generation in one area would be ‘balanced’ by higher production
in another area, even hundreds of kilometres away. Over a year, an
installed offshore wind power capacity of 68.4 GW in the North Sea
would be able to generate an estimated 247 TWh of electricity. An
offshore grid in the North Sea would also allow, for example, the
import of electricity from hydro power generation in Norway to the
British and UCTE (Central European) network. This could replace
thermal baseload plants and increase flexibility within a portfolio. In
addition, increased liquidity and trading facilities on the European
power markets will allow for a more efficient portfolio management.
The value of such an offshore therefore lies in its contribution to
increased security of supply, its function in aggregating the dispatch of
power from offshore wind farms and its role as a facilitator for power
exchange and trade between regions and power systems.
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references
10 ‘RENEWABLE ENERGIES - INNOVATIONS FOR THE FUTURE’, GERMAN MINISTRY FOR
THE ENVIRONMENT, NATURE CONSERVATION AND NUCLEAR SAFETY (BMU), 2006